ceph/src/rgw/rgw_period_puller.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab ft=cpp
   3
   4 #include "rgw_rados.h"
   5 #include "rgw_zone.h"
   6 #include "rgw_rest_conn.h"
   7 #include "common/ceph_json.h"
   8 #include "common/errno.h"
   9
  10 #include "services/svc_zone.h"
  11
  12 #define dout_subsys ceph_subsys_rgw
  13
  14 #undef dout_prefix
  15 #define dout_prefix (*_dout << "rgw period puller: ")
  16
  17 RGWPeriodPuller::RGWPeriodPuller(RGWSI_Zone *zone_svc, RGWSI_SysObj *sysobj_svc)
  18 {
  19   cct = zone_svc->ctx();
  20   svc.zone = zone_svc;
  21   svc.sysobj = sysobj_svc;
  22 }
  23
  24 namespace {
  25
  26 // pull the given period over the connection
  27 int pull_period(RGWRESTConn* conn, const std::string& period_id,
  28                 const std::string& realm_id, RGWPeriod& period,
  29                 optional_yield y)
  30 {
  31   rgw_user user;
  32   RGWEnv env;
  33   req_info info(conn->get_ctx(), &env);
  34   info.method = "GET";
  35   info.request_uri = "/admin/realm/period";
  36
  37   auto& params = info.args.get_params();
  38   params["realm_id"] = realm_id;
  39   params["period_id"] = period_id;
  40
  41   bufferlist data;
  42 #define MAX_REST_RESPONSE (128 * 1024)
  43   int r = conn->forward(user, info, nullptr, MAX_REST_RESPONSE, nullptr, &data, y);
  44   if (r < 0) {
  45     return r;
  46   }
  47
  48   JSONParser parser;
  49   r = parser.parse(data.c_str(), data.length());
  50   if (r < 0) {
  51     lderr(conn->get_ctx()) << "request failed: " << cpp_strerror(-r) << dendl;
  52     return r;
  53   }
  54
  55   try {
  56     decode_json_obj(period, &parser);
  57   } catch (const JSONDecoder::err& e) {
  58     lderr(conn->get_ctx()) << "failed to decode JSON input: "
  59         << e.what() << dendl;
  60     return -EINVAL;
  61   }
  62   return 0;
  63 }
  64
  65 } // anonymous namespace
  66
  67 int RGWPeriodPuller::pull(const std::string& period_id, RGWPeriod& period,
  68                           optional_yield y)
  69 {
  70   // try to read the period from rados
  71   period.set_id(period_id);
  72   period.set_epoch(0);
  73   int r = period.init(cct, svc.sysobj, y);
  74   if (r < 0) {
  75     if (svc.zone->is_meta_master()) {
  76       // can't pull if we're the master
  77       ldout(cct, 1) << "metadata master failed to read period "
  78           << period_id << " from local storage: " << cpp_strerror(r) << dendl;
  79       return r;
  80     }
  81     ldout(cct, 14) << "pulling period " << period_id
  82         << " from master" << dendl;
  83     // request the period from the master zone
  84     r = pull_period(svc.zone->get_master_conn(), period_id,
  85                     svc.zone->get_realm().get_id(), period, y);
  86     if (r < 0) {
  87       lderr(cct) << "failed to pull period " << period_id << dendl;
  88       return r;
  89     }
  90     // write the period to rados
  91     r = period.store_info(true, y);
  92     if (r == -EEXIST) {
  93       r = 0;
  94     } else if (r < 0) {
  95       lderr(cct) << "failed to store period " << period_id << dendl;
  96       return r;
  97     }
  98     // update latest epoch
  99     r = period.update_latest_epoch(period.get_epoch(), y);
 100     if (r == -EEXIST) {
 101       // already have this epoch (or a more recent one)
 102       return 0;
 103     }
 104     if (r < 0) {
 105       lderr(cct) << "failed to update latest_epoch for period "
 106           << period_id << dendl;
 107       return r;
 108     }
 109     // reflect period objects if this is the latest version
 110     if (svc.zone->get_realm().get_current_period() == period_id) {
 111       r = period.reflect(y);
 112       if (r < 0) {
 113         return r;
 114       }
 115     }
 116     ldout(cct, 14) << "period " << period_id
 117         << " pulled and written to local storage" << dendl;
 118   } else {
 119     ldout(cct, 14) << "found period " << period_id
 120         << " in local storage" << dendl;
 121   }
 122   return 0;
 123 }